addOnloadEvent(init_show);
function init_show() {
	var slide_div0 = document.getElementById("box1");
	var slide_div1 = document.getElementById("box2");
	slide_show(slide_div0);
	slide_show(slide_div1);
	/*
	slide_div = document.getElementsByName("slide_show");
	for(i = 0; i < slide_div.length; i++) {
		slide_show(slide_div[i]);
	}
	*/
}

function slide_show(div) {
//	var oBox = document.getElementById("box");
//	var aUl = document.getElementsByTagName("ul");
	var oBox = div;
	var aUl = div.getElementsByTagName("ul");
	var aImg = aUl[0].getElementsByTagName("li");
	var aNum = aUl[1].getElementsByTagName("li");
	var timer = play = null;
	var i = index = 0;	
	//切换按钮
	for (i = 0; i < aNum.length; i++)
	{
		aNum[i].index = i;
		aNum[i].onmouseover = function ()
		{
			show(this.index)
		}
	}
	//鼠标划过关闭定时器
	oBox.onmouseover = function ()
	{
		clearInterval(play)	
	};
	
	//鼠标离开启动自动播放
	oBox.onmouseout = function ()
	{
		autoPlay()
	};	
	
	//自动播放函数
	function autoPlay ()
	{
		play = setInterval(function () {
			index++;
			index >= aImg.length && (index = 0);
			show(index);		
		},2000);	
	}
	autoPlay();//应用
	//图片切换, 淡入淡出效果
	function show (a)
	{
		index = a;
		var alpha = 0;
		for (i = 0; i < aNum.length; i++)aNum[i].className = "";
		aNum[index].className = "current";
		clearInterval(timer);			
		
		for (i = 0; i < aImg.length; i++)
		{
			aImg[i].style.opacity = 0;
			aImg[i].style.filter = "alpha(opacity=0)";	
		}
		
		timer = setInterval(function () {
			alpha += 2;
			alpha > 100 && (alpha =100);
			aImg[index].style.opacity = alpha / 100;
			aImg[index].style.filter = "alpha(opacity = " + alpha + ")";
			alpha == 100 && clearInterval(timer)
		},20);
	}
}

function addOnloadEvent(func) {
	var oldonload = window.onload;
	if(typeof(oldonload) != 'function') {
		window.onload = func;
	} else {
		window.onload = function() {
			oldonload();
			func();
		}
	}
}
